Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c538459af80e068…

MALICIOUS

PDF

61.2 KB
MD5: d593735375594f7df42fa1619a9b12c7 SHA-1: b878faa3ae4bb239647ab2dae8d766edf656d1a7 SHA-256: 8c538459af80e0688742fefe931514ff6231564eb3bd423bf26ba8f1bbb4a276
358 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1059.001 Command and Scripting Interpreter: JavaScript T1566.001 Phishing: Spearphishing Attachment T1190 Exploit Public-Facing Application

The PDF file contains embedded JavaScript that utilizes character-table indexing for obfuscation, a technique commonly used to evade static analysis. Critical heuristics indicate exploitation of multiple CVEs (2009-4324, 2009-0927, 2007-5659, 2008-2992) related to JavaScript execution within Adobe Reader. The deobfuscated JavaScript is likely responsible for downloading and executing a secondary payload, as suggested by the 'eval_char_append_stage_000.js' filename and the heuristic 'PDF_JS_CHAR_TABLE_EVAL_STAGER'.

Heuristics 9

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36310 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36310
  • Character-table JavaScript eval stager high PDF_JS_CHAR_TABLE_EVAL_STAGER
    PDF JavaScript reconstructs an exploit stage by indexing into a small character table, appending hundreds of one-character fragments, joining the array, and evaluating the result. This static fallback fires only after the bounded decoder recovers an exploit-like stage, so it catches this obfuscation even when no single CVE API signature is available.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0076_000.js
d59faa7518f4d9fb058ceb7c0afbfb7efc208f673544f0abb8b45a524ce45391
pdf-javascript-stream PDF /JS object 76 at offset 0x2D4 53993 bytes
eval_char_append_stage_000.js
05ee86497474e5860b81e45875a2e015cc8eb5f147ddaa68a17cbd53b2cfd16b
deobfuscated-js eval character-table append decoded JavaScript at offset 0x300 3870 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).